Yanmar 2YM15, Service Manual

Page: 144 / 231

5. Inspection and servicing of basic engine parts
124R1
5.4.3 Piston pin bushing
(1) Measuring piston pin clearance.
Excessive piston pin bushing wear may result in
damage to the piston pin or the piston itself.
Measure the piston pin bushing inside diameter and
the piston pin outside diameter. Calculate the oil
clearance from the measured values. (Refer to 5.3.2
for the piston pin.)
5.4.4 Assembling piston and connecting
rod
The piston and connecting rod should be assembled so
that the match mark on the connecting rod large end
faced the fuel nozzle side and the combustion chamber
above the piston is close to the fuel nozzle.
mm
Standard Limit
Piston pin metal
I.D.
22.025-22.038 22.068
Pin O.D. 21.991-22.000 21.963
Clearance 0.025-0.047 0.105
Cylinder gage
(Connecting rod small end)
Piston ID mark
(Camshaft side)
(Nozzle side)
Piston ID mark
Embossed mark
(Flywheel side)
Match mark
Cylinder size mark
(Flywheel side)
Assembly direction of connecting
rod and piston
( )